Twitter logo is displayed at the entrance of Twitter headquarters in San Francisco. (AFP/Getty Images)

SAN FRANCISCO (KCBS) – Both public and private sector leaders agree San Francisco has become a major driver of the high-tech community, with the growth of social media pushing the boundaries of what is considered Silicon Valley.

Geographically speaking, San Francisco can never be in Silicon Valley, but the city now occupies a pivotal place in the Valley’s high-tech culture.

“It really is an extension of Silicon Valley in that the ecosphere is here,” said Bill Coleman, a partner at the venture capital firm Alsop Louie Ventures, who after 30 years, recently moved his offices north to tap into a growing community of second and third generation entrepreneurs, tech savvy law firms and fellow investors hunting for the next big thing.

KCBS’ Matt Bigler Reports:

“With the social networking, there’s a whole new kind of investment going on,” he said, adding that the social aspects of San Francisco itself gelled with the increasingly younger workforce at social media companies.

“The social side, that’s a whole new dimension and it’s really where San Francisco shines,” Coleman said.

Those thoughts were echoed by David Chiu, president of the San Francisco Board of Supervisors.

“Having this hub of social activity so that people are hanging out by the food trucks, hanging out by the street corner and thinking of that next big idea, that’s an exciting trend,” Chiu said.

Chiu and San Jose Mayor Chuck Reed both agreed the migration north, despite notable exceptions like Facebook, makes it even more pressing for cities to work together on regional issues such as transportation.

“If you look at the long-term growth of the valley, we have to have that transportation infrastructure or else it’s just going to get more and more crowded. And then companies will have more and more reasons to leave,” Reed said.

Both Reed and Chiu spoke about the need for better transportation Wednesday at a “Game Changers” forum in Santa Clara.

Reed said a Bay Area Rapid Transit station in San Jose and more frequent Caltrain service possible with electrification of the tracks will both go a long way to relieving pressure on already crowded freeways that connect San Jose and San Francisco.

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